read_history_file crashes with empty/invalid TERM

[blueyed]

testing/test_pdb.py:258: in test_config_terminalformatter
    __import__('pdb').set_trace()
pdb.py:1417: in set_trace
    pdb = Pdb(start_lineno=lineno, start_filename=filename, **kwds)
pdb.py:183: in __init__
    self.config.setup(self)
../../.pdbrc.py:230: in setup
    configure_readline(pdb.start_filename, pdbcls=pdb.__class__)
../../.pdbrc.py:72: in configure_readline
    readline.read_history_file(histfile)
../pyrepl-git/pyrepl/readline.py:293: in read_history_file
    history = self.get_reader().history
../pyrepl-git/pyrepl/readline.py:207: in get_reader
    console = UnixConsole(self.f_in, self.f_out, encoding=ENCODING)
../pyrepl-git/pyrepl/unix_console.py:123: in __init__
    curses.setupterm(term, self.output_fd)
../pyrepl-git/pyrepl/_minimal_curses.py:58: in setupterm
    raise error("setupterm() failed (err=%d)" % err.value)
E   pyrepl._minimal_curses.error: setupterm() failed (err=-1)